Hi, welcome to the forum. What medications does she currently take? You mentioned she's in a flare, is she taking prednisone? That medication can definitely cause mood swings. The flare itself might also be causing the depression - that's a very common flare symptom. Once the flare gets more under control, the depression should start to lift at least somewhat. And presuming she's on prednisone for the flare, as she starts to wean off it by gradually lowering the dose, those mood swings should also ease up. So just hang in there!
I'm sure she's going through a lot and maybe wants to keep some of it to herself as this isn't exactly a sexy illness. The way I try to explain it to people is like this - think back to the worst stomach bug you've ever had. Nausea, diarrhea, can't eat anything, no appetite, can't get out of the bathroom. Now think back to the worst respiratory flu you've ever had - the aches, the chills, the incredible fatigue, no energy. Now, take those two thoughts, put them together, and double them. That's basically what a bad flare feels like. It is a little different for all of us (like, some of us have blood in the stool and others don't, some have tons of pain and others have little pain), but that's a good general way of thinking about what a flare feels like. Your girlfriend is dealing with a lot of nasty symptoms, even if she's not letting a lot of it show. And unfortunately there isn't a way for you to "fix" things, but you can provide a listening ear if she wants to talk - you could also encourage her to post here on the forum, we all deal with this stuff so we can relate to what she's going through, and nothing is TMI on here.
As for how you can help - do you two live together? If so, try to help as much as you can with the housework. Cleaning, vacuuming, laundry, dishes, etc - those things take so much effort in a flare (even taking a shower can be a monumental task during a flare). Listen to her if she wants to talk, but don't push her into sharing the gory details if she doesn't want to. If she brings you along to doctor appointments, take notes for her in case she doesn't remember later everything that the doctor said. Also do some research on the illness so that you can ask informed questions of the doctor. (I wish my husband would do that, but he's clueless in that regard - similar to what you said, he just wishes there was a magic way to make everything better, and he gets frustrated when he can't fix things.)
Distractions from the flare are also really good things. I had my worst flare ever last year and it was the first time I was hospitalized. My husband brought me some lego sets to the hospital, and that was really great. It wasn't too physical of a task nor too difficult, but it was fun and distracting to put together legos. It distracted me from the horribleness of the flare and the hospital for a little while. Those coloring books for grown-ups are also a good distraction. And if she does crafts like knitting or crocheting, that could also be a good thing for her. I like to feel worthwhile when I'm flaring, and if I can crochet a scarf or a blanket, that does make me feel worthwhile. I'm doing something useful and I end up with a finished product that I can use or sell on etsy or give as a gift. So do help her find some fun distractions, things that don't require a lot of physical effort.
I hope that was slightly helpful. Good luck! Your heart is definitely in the right place!
